1. Field of the Invention
The present invention is generally related to a self adjusting switch mechanism and, more specifically, to a switch mechanism intended for use with an appliance and provided for the purpose of adjusting the position of a switch so that complicated assembly and calibration procedures can be avoided.
2. Description of the Prior Art
Many different types of switches have been used by those skilled in the art. Certain switches are used in association with appliances, such as washing machines and dishwashers. One particular application for a switch in an appliance is to detect the closure of a door so that operation of the appliance can be terminated when the door is opened. For example, when the door of a washing machine is opened, the operation of the washing machine is stopped for safety purposes.
When a switch is used to detect the open or closed status of an appliance door, the switch is typically actuated by the movement of an actuating bar or bracket attached to the door. When the door is opened, the bar or bracket moves away from contact with the switch actuator and an electrical circuit is opened for the purpose of stopping the operation of the device. When a switch of this type is attached to a stationary portion of the appliance, it must be positioned with sufficient accuracy to cause the switch to be actuated in response to movement of the door. Since the appliance door, the actuating bar or rod and the housing are all manufactured within certain tolerance ranges, the accumulation of tolerances occasionally causes the position of the actuator bar or rod to differ from its intended position relative to the switch actuator or plunger. When this occurs, the realized travel exceeds or falls short of the expected travel of the rod or actuator bar which is necessary to actuate the switch. When this occurs, physical movement of the switch is necessary and the position of the switch must be calibrated to assure that movement of the appliance door will cause the switch plunger to move from a deactuated position to an actuated position. In addition, the switch must be properly positioned to prevent damage from occurring to the switch when the door is closed.
It would therefore be beneficial if a self adjusting switch mechanism could be provided in order to automatically position the switch relative to the stationary and movable portions of the appliance so that movement of the door will depress the switch actuator, or plunger, by the appropriate amount without causing damage to the switch and without providing insufficient movement of the switch plunger.